Intervention effects and related mechanisms of glycyrrhizic acid on zebrafish with Hirschsprung-associated enterocolitis.

BACKGROUND: The prevention and treatment of Hirschsprung-associated enterocolitis (HAEC) is a serious challenge in pediatric surgery. Exploring the mechanism of HAEC is conducive to the prevention of this disease. AIM: To explore the possible mechanism of glycyrrhizic acid (GA) and its therapeutic effect on HAEC. METHODS: We developed a model of enteritis induced by trinitrobenzenesulfonic acid (TNBS) in zebrafish, and treated it with different concentrations of GA. We analyzed the effect of GA on the phenotype and inflammation of zebrafish. RESULTS: After treatment with TNBS, the area of the intestinal lumen in zebrafish was significantly increased, but the number of goblet cells in the intestinal lumen was significantly reduced, but these did not increase the mortality of zebrafish, indicating that the zebrafish enteritis model was successfully developed. Different concentrations of GA protected zebrafish with enteritis. In particular, high concentrations of GA were important for the prevention and control of HAEC because it significantly reduced the intestinal luminal area, increased the number of goblet cells in the intestinal lumen, and reduced the levels of interleukin (IL)-1ß and IL-8. CONCLUSION: GA significantly reduced the intestinal luminal area, increased the number of intestinal goblet cells, and decreased IL-1ß and IL-8 in zebrafish, and is important for prevention and control of HAEC.

Proteomic Distributions in CD34+ Microvascular Niche Patterns of Glioblastoma.

The poor clinical prognosis and microvascular patterns of glioblastoma (GBM) are of serious concern to many clinicians and researchers. However, very few studies have examined the correlation between microvascular niche patterns (MVNPs) and proteomic distribution. In this study, CD34 immunofluorescence staining and matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-IMS) technology were used to investigate the protein distributions in MVNPs. CD34+ microvascular phenotype could be divided into four types: microvascular sprouting (MS), vascular cluster (VC), vascular garland (VG), and glomeruloid vascular proliferation (GVP). Based on such characteristics, MVNPs were divided into two types by cluster analysis, namely, type I, comprising primarily MS and VC, and type II, comprising many VGs and GVPs. Survival analysis indicated the type of MVNPs to be an independent prognostic factor for progression-free and overall survival in GBM. MALDI-IMS results showed the peaks at m/z 1037 and 8960 to exhibit stronger ion signals in type II, while those at m/z 3240 and 3265 exhibited stronger ion signals in type I. The findings may assist future research on therapy and help predict prognosis in GBM. However, due to the limited number of studies, more well-designed studies are warranted to further verify our results.

Development and Validation of Prognostic Nomograms Based on Gross Tumor Volume and Cervical Nodal Volume for Nasopharyngeal Carcinoma Patients With Concurrent Chemoradiotherapy.

PURPOSE: Our study aimed to establish and validate prognostic nomograms based on gross tumor volume (GTV) and cervical nodal volume (CNV) for nasopharyngeal carcinoma (NPC) patients treated with two cycles of concurrent chemoradiotherapy (CCRT). METHODS: From 2012 to 2015, 620 eligible patients who received radical treatment at the Cancer Hospital of Shantou University Medical College were recruited for a nomogram study. Variables were determined in a training set of 463 patients from 2012 to 2014 by X-tile analysis, univariate and multivariate Cox proportional hazard analyses, and the least absolute shrinkage and selection operator (LASSO). Another cohort of 157 patients in 2015 was validated with bootstrap resampling. The concordance index (C-index) and calibration curves were applied to assess its predictive discriminative and accuracy ability, while decision curve analysis (DCA), X-tile analysis and Kaplan-Meier curve for clinical application. RESULTS: Independent prognostic variables for overall survival (OS) were age, GTV, CNV, cranial nerve, positive cervical lymph node laterality below the caudal border of cricoid cartilage (LNBC), and were selected for the nomogram. Optimal prognostic factors including Karnofsky performance status (KPS), age, GTV, CNV, LNBC were incorporated in the nomogram for progression-free survival (PFS). In the training set, the C-index of our nomograms for OS and PFS were 0.755 (95% CI, 0.704 to 0.807) and 0.698 (95% CI, 0.652 to 0.744). The calibration curve showed good agreement between nomogram-predicted and actual survival. DCA indicated that our nomograms were of clinical benefit. CONCLUSION: Our nomograms are capable of effective prognostic prediction for patients with NPC.

Nestin+/CD31+ cells in the hypoxic perivascular niche regulate glioblastoma chemoresistance by upregulating JAG1 and DLL4.

BACKGROUND: Failure of glioblastoma (GBM) therapy is often ascribed to different types of glioblastoma stem-like cell (GSLC) niche; in particular, a hypoxic perivascular niche (HPVN) is involved in GBM progression. However, the cells responsible for HPVNs remain unclear. METHODS: Immunostaining was performed to determine the cells involved in HPVNs. A hypoxic chamber and 3-dimensional (3D) microfluidic chips were designed to simulate a HPVN based on the pathological features of GBM. The phenotype of GSLCs was evaluated by fluorescence scanning in real time and proliferation and apoptotic assays. The expression of JAG1, DLL4, and Hes1 was determined by immunostaining, ELISA, Western blotting, and quantitative PCR. Their clinical prognostic significance in GBM HPVNs and total tumor tissues were verified by clinical data and The Cancer Genome Atlas databases. RESULTS: Nestin+/CD31+ cells and pericytes constitute the major part of microvessels in the HPVN, and the high ratio of nestin+/CD31+ cells rather than pericytes are responsible for the poor prognosis of GBM. A more real HPVN was simulated by a hypoxic coculture system in vitro, which consisted of 3D microfluidic chips and a hypoxic chamber. Nestin+/CD31+ cells in the HPVN were derived from GSLC transdifferentiation and promoted GSLC chemoresistance by providing more JAG1 and DLL4 to induce downstream Hes1 overexpression. Poor GBM prognosis correlated with Hes1 expression of tumor cells in the GBM HPVN, and not with total Hes1 expression in GBM tissues. CONCLUSIONS: These results highlight the critical role of nestin+/CD31+ cells in HPVNs that acts in GBM chemoresistance and reveal the distinctive prognostic value of these molecular markers in HPVNs.

Induction chemotherapy followed by concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma: long-term results of a phase III multicentre randomised controlled trial.

BACKGROUND: Initial 3-year results from our clinical trial in locoregionally advanced nasopharyngeal carcinoma (NPC) patients showed that induction chemotherapy (IC) with cisplatin and fluorouracil resulted in improved disease-free survival (DFS) with a marginally significant effect on distant metastasis-free survival (DMFS), but the effect of IC on locoregional relapse-free survival and overall survival (OS) did not differ significantly. Here, we present 5-year follow-up results. PATIENTS AND METHODS: Our trial was a randomised, open-label phase III trial comparing IC followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in patients with stage III-IVB (except T3N0-1) NPC. The IC followed by CCRT group received cisplatin (80 mg/m2 d1) and fluorouracil (800 mg/m2 d1-5) every 3 weeks for two cycles before CCRT. Both groups were treated with 80 mg/m2 cisplatin every 3 weeks concurrently with radiotherapy. The primary end-points were DFS and DMFS. We did efficacy analyses in the 476 randomised patients (intention-to-treat population). RESULTS: After a median follow-up of 82.6 months, the 5-year DFS rate was 73.4% (95% confidence interval [CI] 67.7-79.1) in the IC followed by CCRT group and 63.1% (95% CI 56.8-69.4) in the CCRT alone group (p = 0.007). The 5-year DMFS rate was also significantly higher in the IC followed by CCRT group (82.8%, 95% CI 77.9-87.7) than in the CCRT alone group (73.1%, 95% CI 67.2-79.0, p = 0.014). Our updated analysis revealed an OS benefit of IC: the 5-year OS rate was 80.8% in the IC followed by CCRT group versus 76.8% in the CCRT alone group (p = 0.040). The proportion of patients with eye damage was significantly higher in the CCRT alone group than the IC followed by CCRT group (16.4% [39/238] versus 9.7% [23/238], p = 0.029). CONCLUSION: IC followed by CCRT provides long-term DFS, DMFS and OS benefits compared with CCRT alone in locoregionally advanced NPC and, therefore, can be recommended for these patients.

Bioactivity and safety of chimeric switch receptor T cells in glioblastoma patients.

Experimental evidence has shown that chimeric switch receptor T (CSR-T) cells, activated by binding programmed death-ligand 1 on the tumor cell surface, lead to tumor regression in experimental animals. In this phase I clinical study, we evaluated the safety and bioactivity of CSR-T cell therapy in 14 patients with recurrent glioblastoma who were unresponsive to surgical resection and standard radiotherapy. Patients who received 108 CSR-T cells either intravenously or intracranially showed an increase in the levels of IFN-gamma and IL-6, respectively, in peripheral blood or cerbrospinal fluid (CSF). Moreover, the number of T cells present in CSF significantly increased after the treatment. Patients did not show grade 3 or 4 adverse effects. The evidence of in vivo biological activity and lack of adverse effects of treatment with CSR-T cells suggest that such treatment can be subjected to further analysis to show the efficacy of this new treatment strategy in the treatment of cancers that are not responsive to traditional therapeutic regimens.

Overexpression of long noncoding RNA LINC01419 in esophageal squamous cell carcinoma and its relation to the sensitivity to 5-fluorouracil by mediating GSTP1 methylation.

BACKGROUND: Genome-wide sequencing investigations have identified numerous long noncoding RNAs (lncRNAs) among mammals, many of which exhibit aberrant expression in cancers, including esophageal squamous cell carcinoma (ESCC). Herein, this study elucidates the role and mechanism by which LINC01419 regulates the DNA methylation of glutathione S-transferase pi 1 (GSTP1) in relation to ESCC progression and the sensitivity of ESCC cells to 5-fluorouracil (5-FU). METHODS: LINC01419 and GSTP1 levels were quantified among 38 paired ESCC and adjacent tissue samples collected from patients with ESCC. To ascertain the contributory role of LINC01419 in the progression of ESCC and identify the interaction between LINC01419 and GSTP1 promoter methylation, LINC01419 was overexpressed or silenced, and the DNA methyltransferase inhibitor 5-Aza-CdR was treated. RESULTS: Data from the GEO database (GSE21362) and the Cancer Genome Atlas displayed elevated levels of LINC01419 and downregulated levels of GSTP1 in the ESCC tissues and cells. The silencing of LINC01419 led to decreased proliferation, increased apoptosis, and enhanced sensitivity to 5-FU in ESCC cells. Notably, LINC01419 could bind to the promoter region of the GSTP1 gene, resulting in elevated GSTP1 methylation and reduced GSTP1 levels via the recruitment of DNA methyltransferase among ESCC cells, whereby ESCC progression was stimulated accompanied by reduced ESCC cell sensitivity to 5-FU. GSTP1 demethylation by 5-Aza-CdR was observed to reverse the effects of LINC01419 overexpression in ESCC cells and the response to 5-FU. CONCLUSION: Highly expressed LINC01419 in ESCC promotes GSTP1 methylation, which ultimately acts to promote the event of ESCC and diminish the sensitivity of ESCC cells to 5-FU, highlighting a novel potential strategy to improve 5-FU-based chemotherapy in ESCC.

Reconstituting Glioma Perivascular Niches on a Chip for Insights into Chemoresistance of Glioma.

In this work, we report the direct diagnosing chemoresistance of glioma stem cells (GSCs) during chemotherapy on a biomimetric microsystem that reconstitutes glioma perivascular niches on a chip. Glioma stem cells and endothelial cells were specially cocultured onto the biomimetric system to precisely control stem cell coculture for the proof-of-principle studies. The expression levels of 6- O-methylguanine was confirmed by mass spectrometer, and Bmi-1 gene was also investigated to uncover the chemoresistance of GSCs. The results demonstrated that the formation of perivascular niches effectively maintains the glioma stem cells at a pluripotent status owing to their successful cellular interactions. A stronger chemoresistance of glioma stem cells was confirmed by the formation of the GSCs neurosphere, the expression levels of 6- O-methylguanine and Bmi-1 gene. The vital role of endothelial cells in chemoresistance was demonstrated. The chemoresistance reported in this work will contribute to glioma therapy.

Genetic analysis of three porcine bocaparvoviruses and identification of a natural recombinant breakpoint in NS1.

In this study, we obtained the whole genomes of three porcine bocaparvovirus (PBoV) strains (GD6, GD10, and GD23) by polymerase chain reaction. Sequence analysis showed that all three field strains belonged to PBoV group 3 (G3). The phylogenetic trees based on NS1, NP1, and VP1 differed to the extent that these PBoVs were potentially more closely related to bocaparvoviruses known to infect other animals than to other PBoVs. GD6, GD10, and GD23 all included the conserved sequences YLGPF and HDXXY, with known phospholipase A2 activity. Using recombination-detection software we identified a natural recombinant breakpoint in the NS1 region of PBoV G3. The results of this study will further the epidemiological characterization of PBoVs.

Improving the prediction of overall survival for head and neck cancer patients using image biomarkers in combination with clinical parameters.

PURPOSE: To develop and validate prediction models of overall survival (OS) for head and neck cancer (HNC) patients based on image biomarkers (IBMs) of the primary tumor and positive lymph nodes (Ln) in combination with clinical parameters. MATERIAL AND METHODS: The study cohort was composed of 289 nasopharyngeal cancer (NPC) patients from China and 298 HNC patients from the Netherlands. Multivariable Cox-regression analysis was performed to select clinical parameters from the NPC and HNC datasets, and IBMs from the NPC dataset. Final prediction models were based on both IBMs and clinical parameters. RESULTS: Multivariable Cox-regression analysis identified three independent IBMs (tumor Volume-density, Run Length Non-uniformity and Ln Major-axis-length). This IBM model showed a concordance(c)-index of 0.72 (95%CI: 0.65-0.79) for the NPC dataset, which performed reasonably with a c-index of 0.67 (95%CI: 0.62-0.72) in the external validation HNC dataset. When IBMs were added in clinical models, the c-index of the NPC and HNC datasets improved to 0.75 (95%CI: 0.68-0.82; p=0.019) and 0.75 (95%CI: 0.70-0.81; p<0.001), respectively. CONCLUSION: The addition of IBMs from the primary tumor and Ln improved the prognostic performance of the models containing clinical factors only. These combined models may improve pre-treatment individualized prediction of OS for HNC patients.

The pathological structure of the perivascular niche in different microvascular patterns of glioblastoma.

The perivascular niche is critical for intercellular communication between resident cell types in glioblastoma (GBM), and it plays a vital role in maintaining the glioma stem cell (GSC) microenvironment. It is shown in abundant research that different microvascular patterns exist in GBM; and it can be implied that different microvascular patterns are associated with different pathological structures in the perivascular niche. However, the pathological structure of the perivascular niche is still not clear. Here, we investigated the distribution and biological characteristics of different microvascular pattern niches (MVPNs) in GBM by detecting the expression of CD34, CD133, Nestin, α-SMA, GFAP and CD14 in the perivascular niche using multiple -fluorescence. The four basic microvascular patterns are microvascular sprouting (MS), vascular cluster (VC), vascular garland (VG), and glomeruloid vascular proliferation (GVP). By analyzing the proportion of the area of each marker in four types of formations, the results indicated that the expression of CD34, CD133 and Nestin in MS and VC was significantly lower than that in VG and GVP (P<0.05). Furthermore, the results showed that α-SMA expression different in the MS, VC, VG and GVP (P<0.05). However, the expression of GFAP and CD14 in each type of formation exhibited no significant difference (P>0.05). According to the area distributions of different markers, we mapped four precise simulation diagrams to provide an effective foundation for the accurate simulation of glioblastoma in vitro.

Neoadjuvant chemotherapy followed by concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma: A phase III multicentre randomised controlled trial.

BACKGROUND: The role of neoadjuvant chemotherapy (NACT) for locoregionally advanced nasopharyngeal carcinoma (NPC) is unclear. We aimed to evaluate the feasibility and efficacy of NACT followed by concurrent chemoradiotherapy (CCRT) versus CCRT alone in locoregionally advanced NPC. METHODS: Patients with stage III-IVB (excluding T3N0-1) NPC were randomly assigned to receive NACT followed by CCRT (investigational arm) or CCRT alone (control arm). Both arms were treated with 80 mg/m2 cisplatin every 3 weeks concurrently with radiotherapy. The investigational arm received cisplatin (80 mg/m2 d1) and fluorouracil (800 mg/m2 civ d1-5) every 3 weeks for two cycles before CCRT. The primary end-point was disease-free survival (DFS) and distant metastasis-free survival (DMFS). Secondary end-point was overall survival (OS). Survival curves for the time-to-event endpoints were analyzed by the Kaplan-Meier method and compared using the log-rank test. The P value was calculated using the 5-year endpoints. RESULTS: Four hundred seventy six patients were randomly assigned to the investigational (n = 238) and control arms (n = 238). The investigational arm achieved higher 3-year DFS rate (82.0%, 95% CI = 0.77-0.87) than the control arm (74.1%, 95% CI = 0.68-0.80, P = 0.028). The 3-year DMFS rate was 86.0% for the investigational arm versus 82.0% for the control arm, with marginal statistical significance (P = 0.056). However, there were no statistically significant differences in OS or locoregional relapse-free survival (LRRFS) rates between two arms (OS: 88.2% versus 88.5%, P = 0.815; LRRFS: 94.3% versus 90.8%, P = 0.430). The most common grade 3-4 toxicity during NACT was neutropenia (16.0%). During CCRT, the investigational arm experienced statistically significantly more grade 3-4 toxicities (P < 0.001). CONCLUSION: NACT improved tumour control compared with CCRT alone in locoregionally advanced NPC, particularly at distant sites. However, there was no early gain in OS. Longer follow-up is needed to determine the eventual therapeutic efficacy.

A dosimetric and treatment efficiency evaluation of stereotactic body radiation therapy for peripheral lung cancer using flattening filter free beams.

To investigate potential dosimetric benefits and treatment efficiency of dynamic conformal arc therapy (DCA), intensity modulated radiation therapy (IMRT), and double partial arcs Rapidarc (RA) techniques in the treatment of early-stage peripheral lung cancer using stereotactic body radiotherapy (SBRT) with flattening filter free (FFF) beams. Twenty early-stage peripheral lung cancer patients were selected. For each patient, DCA, IMRT and RA plans were created to meet Radiation Therapy Oncology Group (RTOG) 0915 objectives with 48 Gy covering 95% of the planning target volume (PTV) in 4 fractions. PTV coverage, organs at risk (OARs) doses, planning time, monitor units (MU) and treatment time were evaluated. RA was significantly better than DCA for PTV coverage. RA provided a lower V32Gy to chest wall and less V20Gy to lung over those of DCA and IMRT. For other OARs, there is no significant difference among all three techniques. DCA plans showed significantly less planning time, shorter treatment time and lower MU number than those of RA and IMRT. RA provides a superior dosimetric benefit to DCA and IMRT in the treatment of early-stage lung cancer using SBRT with FFF beams. Considering the MU number, planning time and treatment efficiency, DCA technique is an effective treatment strategy.

Effects of omitting elective neck irradiation to nodal Level IB in nasopharyngeal carcinoma patients with negative Level IB lymph nodes treated by intensity-modulated radiotherapy: a Phase 2 study.

OBJECTIVE: To investigate the need for elective neck irradiation (ENI) to nodal Level IB in patients with nasopharyngeal carcinoma (NPC) with negative Level IB lymph nodes (IB-negative) treated by intensity-modulated radiotherapy (IMRT). METHODS: We conducted a Phase 2 prospective study in 123 newly diagnosed IB-negative patients with NPC treated by IMRT, who met at least 1 of the following criteria: (1) unilateral or bilateral Level II involvement with 1 of the following: Level IIA involvement or any Level II node ≥2 cm/with extracapsular spread; (2) ≥2 unilateral node-positive regions. Bilateral Level IB nodes were not contoured as part of the treatment target and treated electively. Level IB regional recurrence rate; pattern of treatment failure; 3-year overall survival (3y-OS), 3-year local control (3y-LC) and 3-year regional control (3y-RC) rates; toxicities; and dosimetric data for planning target volumes, organs at risk, Level IB and submandibular glands (SMGs) were evaluated. RESULTS: Two patients developed failures at Level IB (1.6%). The 3y-LC, 3y-RC and 3y-OS rates were 93.5%, 93.5% and 78.0%, respectively. Bilateral Level IB received unplanned high-dose irradiation with a mean dose (Dmean) ≥50 Gy in 60% of patients. The average Dmean of bilateral SMGs was approximately 53 Gy. CONCLUSION: ENI to Level IB may be unnecessary in IB-negative patients with NPC treated by IMRT. A further Phase 3 study is warranted. ADVANCES IN KNOWLEDGE: Based on the results of this first Phase 2 study, we suggest omitting ENI to Level IB in Ib-negative patients with NPC with extensive nodal disease treated by IMRT.

Dosimetric analysis of isocentrically shielded volumetric modulated arc therapy for locally recurrent nasopharyngeal cancer.

This study aimed to investigate the dosimetric characteristics of an isocentrically shielded RapidArc (IS-RA) technique for treatment of locally recurrent nasopharyngeal cancer (lrNPC). In IS-RA, the isocenter was placed at the center of the pre-irradiated brainstem (BS)/spinal cord (SC) and the jaws were set to shield the BS/SC while ensuring the target coverage during the whole gantry rotation. For fifteen patients, the IS-RA plans were compared with the conventional RapidArc (C-RA) regarding target coverage, organ-at-risk (OAR) sparing and monitor units (MUs). The relationship between the dose reduction of BS/SC and some geometric parameters including the angle extended by the target with respect to the axis of BS/SC (Ang_BSSC), the minimum distance between the target and BS/SC (Dist_Min) and the target volume were evaluated. The IS-RA reduced the BS/SC doses by approximately 1-4 Gy on average over the C-RA, with more MUs. The IS-RA demonstrated similar target coverage and sparing of other OARs except for slightly improved sparing of optic structures. More dose reduction in the isocentric region was observed in the cases with larger Ang_BSSC or smaller Dist_Min. Our results indicated that the IS-RA significantly improves the sparing of BS/SC without compromising dosimetric requirements of other involved structures for lrNPC.

High IFIT1 expression predicts improved clinical outcome, and IFIT1 along with MGMT more accurately predicts prognosis in newly diagnosed glioblastoma.

Interferon-induced protein with tetratricopeptide repeat 1 (IFIT1) plays a key role in growth suppression and apoptosis promotion in cancer cells. Interferon was reported to induce the expression of IFIT1 and inhibit the expression of O-6-methylguanine-DNA methyltransferase (MGMT).This study aimed to investigate the expression of IFIT1, the correlation between IFIT1 and MGMT, and their impact on the clinical outcome in newly diagnosed glioblastoma. The expression of IFIT1 and MGMT and their correlation were investigated in the tumor tissues from 70 patients with newly diagnosed glioblastoma. The effects on progression-free survival and overall survival were evaluated. Of 70 cases, 57 (81.4%) tissue samples showed high expression of IFIT1 by immunostaining. The χ(2) test indicated that the expression of IFIT1 and MGMT was negatively correlated (r = -0.288, P = .016). Univariate and multivariate analyses confirmed high IFIT1 expression as a favorable prognostic indicator for progression-free survival (P = .005 and .017) and overall survival (P = .001 and .001), respectively. Patients with 2 favorable factors (high IFIT1 and low MGMT) had an improved prognosis as compared with others. The results demonstrated significantly increased expression of IFIT1 in newly diagnosed glioblastoma tissue. The negative correlation between IFIT1 and MGMT expression may be triggered by interferon. High IFIT1 can be a predictive biomarker of favorable clinical outcome, and IFIT1 along with MGMT more accurately predicts prognosis in newly diagnosed glioblastoma.

The Vascular Notch Ligands Delta-Like Ligand 4 (DLL4) and Jagged1 (JAG1) Have Opposing Correlations with Microvascularization but a Uniform Prognostic Effect in Primary Glioblastoma: A Preliminary Study.

PURPOSE: Delta-like ligand 4 (DLL4) and Jagged1 (JAG1), 2 vascular Notch ligands, are involved in the process of tumor angiogenesis. The present study investigates their relationship with microvascularization and the prognostic effect in primary glioblastoma. METHODS: Tumor tissues from 61 glioblastomas were analyzed using immunohistochemistry for DLL4/JAG1 expression and microvascular formations. The correlations between DLL4/JAG1 and microvascularization were analyzed. The survival probabilities were computed using the Kaplan-Meier method. The Cox proportional hazards regression model was used for multivariate analysis of time to progression (TTP) and overall survival (OS). RESULTS: The results showed increased DLL4 and JAG1 expression in glioblastoma tissues. Five types of basic microvascular formations, including microvascular sprouting, vascular cluster, vascular garland, glomeruloid vascular proliferation, and vasculogenic mimicry, were detected. Glioblastomas with the type I microvascular pattern (MVP) that displayed prominent microvascular sprouting and vascular clusters tended to have higher DLL4 expression, whereas those with the type II MVP that had numerous vascular garlands, glomeruloid vascular proliferations, and vasculogenic mimicries showed upregulated JAG1 expression. Univariate analysis documented that high DLL4 expression, high JAG1 expression, and type II (MVP) were statistically associated with reduced TTP and OS. Multivariate analysis confirmed high DLL4 expression, high JAG1 expression, and type II MVP as significant prognostic factors for both shorter TTP and OS, independent of age, Karnofsky performance scale, and other molecular markers (vascular endothelial growth factor, Ki67, and P53). CONCLUSIONS: DLL4 and JAG1 may have opposing effects on tumor angiogenesis in glioblastoma. The Notch pathway may be a new target for antiangiogenic therapy in glioblastoma.

The vascular delta-like ligand-4 (DLL4)-Notch4 signaling correlates with angiogenesis in primary glioblastoma: an immunohistochemical study.

Delta-like ligand-4 (DLL4)-Notch signaling is known to play a pivotal role in the regulation of tumor angiogenesis. We had previously found that DLL4 was overexpressed, while Notch1 receptor, which binds to DLL4 during angiogenesis, was absent in the majority of human primary glioblastomas. Thus, DLL4-Notch signaling pathway in the regulation of tumor angiogenesis in primary glioblastoma remains unknown. Tumor tissues from 70 patients with primary glioblastoma were analyzed by immunohistochemistry for expression of components of DLL4-Notch signaling, vascular endothelial growth factor (VEGF), and microvessel density (MVD). Immunohistochemistry results showed that the positive staining of DLL4 and Notch4 was primarily distributed in tumor vascular endothelial cells but rarely detected in tumor cells. However, VEGF, hairy/enhancer of split-1 (HES1; a target gene of Notch signaling), and Notch1-3 expression was seen in both tumor vascular endothelial cells and tumor cells. Univariate analysis showed that the expression levels of VEGF and DLL4, HES1, and Notch4 in tumor endothelial cells were significantly associated with MVD in primary glioblastoma (P < 0.001). Binary logistic regression analysis showed that high expression levels of DLL4, HES1, and Notch4 in tumor endothelial cells were associated with a decrease of MVD in primary glioblastoma, while MVD increased with elevated VEGF expression in contrast. In addition, DLL4, Notch4, and HES1 expression were positively correlated in tumor vascular endothelial cells (P < 0.05). We conclude that the vascular DLL4-Notch4 signaling and VEGF signaling complementing each other plays an important role in the progression of tumor angiogenesis in primary glioblastoma. Graphical abstract A, positive staining of DLL4 in human kidney; B, positive staining of VEGF in human breast cancer; C, positive staining of CD34 in human lung cancer; D, positive staining of HES1 in human breast cancer; E-H, positive staining of Notch1-4: E-F in human lung cancer; G-H in human kidney.